cmake: Make /usr/share/cmake installable with LLVM_DISTRIBUTION_COMPONENTS

Add a cmake-exports install component and appropriate targets for
LLVM_DISTRIBUTION_COMPONENTS to work with.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285030 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed